Jawabanmu

2014-08-24T19:02:16+07:00
Nitrogen (N) Proton : 7 Elektron : 7 Neutron : 14-7 = 7 Kalsium (Ca) Proton 20 Elektron 20 Neutron 40-20 = 20 Kalium (K) Proton 19 Elektron 19 Neutron 39-19 = 20